weblogic.management.ManagementException: Unable to obtain lock on /u03/app/appp/weblogic/user_projects/domains/base_domain/servers/http:/jos2.jacmel.com:7010/tmp/http:/jos2.jacmel.com:7010.lok. Server may already be running
at weblogic.management.internal.ServerLocks.getServerLock(ServerLocks.java:206)
at weblogic.management.internal.ServerLocks.getServerLock(ServerLocks.java:67)
at weblogic.management.internal.DomainDirectoryService.start(DomainDirectoryService.java:74)
at weblogic.t3.srvr.ServerServicesManager.startService(ServerServicesManager.java:461)
at weblogic.t3.srvr.ServerServicesManager.startInStandbyState(ServerServicesManager.java:166)
at weblogic.t3.srvr.T3Srvr.initializeStandby(T3Srvr.java:881)
at weblogic.t3.srvr.T3Srvr.startup(T3Srvr.java:568)
at weblogic.t3.srvr.T3Srvr.run(T3Srvr.java:469)
at weblogic.Server.main(Server.java:71)

Hi,
May be the server is running in previous session. Make sure that the server which started earlier shoud be properly stopped or kill the process id usig "kill -9 pid" command. For changing the port from backend please find the below steps.

Steps:
1. Browse to the config.xml file for the domain:
•Within each domain you will find a config folder (for example, \Middleware_Home\user_projects\domains\<DomainName>\config, and there you will find a config.xml file.
2. Open the config.xml file in a text editor.
3. Browse to the <server> element.
4. Find the AdminServer and change the listening port (between the <listen-port> element) to an unused port.
5. Save and close the file, then restart the Admin Server domain. It will not be started on the new port configured in Step 4.